Conventionally, the visibility of the viewfinder for a camera or the like is fixed to be -1D. Accordingly, myopic persons and hyperopic persons must put a visibility correction lens on the viewfinder in order to accurately focus the camera. The disadvantage of this requirement is that it may be necessary to change the visibility correction lens when the photographer is changed. A further disadvantage is that the visibility correction lens may be lost when it is changed.
Cameras have been proposed which permit the visibility of a viewfinder affixed to the camera to be manually adjusted. When a very presbyopic photographer uses the camera, however, the photographer frequently encounters difficulty in correcting to the desired visibility because the photographer cannot look at the tips of his fingers.
In view of the foregoing problems, an object of the present invention is to provide a viewfinder system in which correction of visibility is automatically performed.